Transformer Sizing

Calculate Primary and Secondary Full Load Amperes (FLA) for standard dry-type distribution transformers.

Phase configuration

Transformer Size (kVA)

Primary Voltage

Secondary Voltage

Pro Tip: Inrush Current

Transformers have severe magnetizing inrush currents. Primary overcurrent protection often needs to be time-delay or inverse-time so it doesn't nuisance trip on energization.

Full Load Amperes (75 kVA)

72.2Primary (A)

208.2Secondary (A)

Rec. Primary Breaker (125%)

Min. Primary Wire (Cu 75°C)-

System Bonding Jumper (Pri)-

Rec. Secondary Breaker (125%)

Min. Secondary Wire (Cu 75°C)-

System Bonding Jumper (Sec)-

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Need to verify complex custom scenarios? Consult Henri to cross-reference exact regulatory requirements for your specific installation condition.

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